This invention relates to cable connectors; and more particularly relates to a novel and improved compression-type connector in which a single size connector is capable of accommodating a wide range of cable sizes.
A problem which has confronted the cable T.V. industry for years has been to provide a single connector size which can accommodate a plurality of different-sized cables. The standard coaxial cable is made up of a center conductor, insulated layer surrounding the conductor, foil layer, braided layer and outer jacket. This is a typical dual shield cable having a single braided layer which is the outer conductor. Depending upon the specific application and frequencies being transmitted through the cable, it is necessary to modify the thickness of the braided layers, and consequently there are dual-shield, tri-shield and quad-shield cables. For example, the quad-shield cable has two braided layers separated by a foil layer. Also, the braided layer may vary in thickness depending upon the frequencies being handled.
U.S. Pat. Nos. 5,863,220 and 6,089,913 disclose coaxial cable connectors that have a crimping ring preassembled onto the connector, and the end of the cable has to be inserted through the single crimping ring and into the inner concentric sleeves on the connector. There are definite size limitations imposed on the diameter of the crimping ring to ensure that it is small enough in diameter to effect the necessary inward contraction on the outer sleeve of the connector to result in a good crimp. This means that the pull-out force necessary to separate the cable from the connector is in excess of 40 psi, and the cable should be contracted enough to assure that there is substantially no leakage or frequency loss between the braided layer(s) and the connector. At the same time, the degree of compression must not be so great as to cause the inner sleeve to collapse or be damaged or otherwise result in an impedance problem in the higher frequency ranges. Especially in larger cables, there is real difficulty in reaching a compromise between the optimum inner diameter of the crimping ring which will permit the cable to be easily inserted into the connector sleeve and the size necessary to effect a good crimp. Since the crimping is most important to assure a good connection, typically the inner diameter of the crimping ring is such that it is very difficult to insert the cable into the connector sleeve. This requires manual dexterity on the part of the installer and, after a day of making connections, can be extremely time-consuming, difficult and very tiring.
Accordingly, for professional installers and home users alike, it is desirable to provide a preassembled crimping ring assembly for a compression-type connector which is conformable for use with a wide range in sizes of coaxial cables either for the purpose of splicing cables together or for connecting one cable end to a terminal and nevertheless be capable of achieving the desired sealed mechanical and electrical connection therebetween.
An object of this invention is to provide for a novel and improved compression-type coaxial cable connector which is readily conformable for use in connecting different size cables either to a terminal or to another connector in a highly efficient and reliable manner.
Another object of the present invention is to provide for a novel and improved end connector for coaxial cables with a self-contained crimping ring assembly to achieve the necessary sealed mechanical and electrical connection between the cable and the terminal or to another cable; and wherein the crimping ring assembly is so constructed and arranged as to bring about the necessary inward radial deformation or compression of the connector into crimping engagement with the cable in response to axial advancement of the crimping ring assembly with existing compression tools.
A further object of the present invention is to provide for a novel and improved cable connector with pre-assembled crimping ring assembly which will effect sealed engagement between the connector and cable in a minimum number of steps and simplified manner.
In accordance with the present invention, a two-stage connector has been devised for mechanically and electrically connecting a cable having a first electrically conductive member to a second electrically conductive member, the connector having a connector body, an outer sleeve extending from an end of the connector body for insertion of an end of the cable therein, a first crimping member having an annular portion including a first inner diameter at least as great as an outer diameter of said outer sleeve and disposed in outer surrounding relation to the outer sleeve, and a second crimping member having a tapered annular portion at least partially overlying the first crimping member wherein slidable axial advancement of the second crimping member and the first crimping member with respect to the outer sleeve will impart radial deformation to the outer sleeve into sealed engagement with an external surface of the cable. Most desirably, the second crimping member has its tapered annular portion extending from a first diameter at least as great as the outer diameter of the outer sleeve to a second diameter less than the outer diameter of the outer sleeve but greater than an inner diameter of the outer sleeve, and the innermost diameter of the first crimping member is also at least as great as the inner diameter of the outer sleeve in order to accommodate different sizes of cable as well as to achieve a higher degree of compression and pull out strength. The preferred form of invention is specifically adaptable for use with coaxial TV cable connectors for terminating a wide range of cable sizes or diameters depending upon the particular application and frequency transmitted.
The above and other objects, advantages and features of the present invention will become more readily appreciated and understood from the following description of preferred and alternative forms of the present invention when taken together with the accompanying drawings, in which: